With the coming and going of any given day's weather, it can be difficult to gauge how Earth’s climate is changing. But NASA scientists have refined a method to measure the planet's annual change in temperature since 1880, the start of the modern meteorological era. What they’ve found is that Earth is getting warmer. In fact, nine of the 10 warmest years on record have occurred since 2000. The method involves comparing the annual average temperature to a 30-year-average taken from 1951 to 1980. By plotting the difference in temperature on a map, researchers can see how Earth’s warming trend has accelerated due to increasing greenhouse gas concentrations in the atmosphere. Watch the video to see how global temperatures have changed from 1950 through 2013.